pH-Sensitive Dye-Polyether Derivatives as Dispersants for Its Parent Dye. Part 2: Dispersion Stability and Dyeing Performance

Abstract

The influence on adsorption of dye-polyether derivatives of different molecular weights and degrees of hydrophilicity/hydrophobicity on the dispersion behavior of C.I. disperse red 60 has been investigated. A range of experimental methods including derivative adsorption isotherms, particle size measurements and dispersion stability tests were used to assess the dispersing capability of the derivatives. The adsorption mainly depends on the hydrophobicity of the derivative but its molecular weight, while the dispersion stability is related to both the adsorption layer and the hydration layer. The results showed that good dispersion stability were obtained even when the weight ratio of dye/dye-polyether derivative was quite low. The dyeing performance of the prepared dispersions was also evaluated by comparing with that of commercial dye. The chemical oxygen demand of the dyeing effluent could be reduced dramatically by the adoption of the dye-polyether derivatives, while the dye exhaustion was higher and the quality of the dyed polyester fabric was at least as good as the dyeing with the commercial dye.

Keywords:

• Adsorption isotherm
• disperse dye
• dispersion stability
• dye-polyether derivative
• dyeing performance

The authors gratefully acknowledge the financial support for this work from the National Natural Science Foundation of China (No. 20973063), the Innovation Foundation for Ph.D candidate of Donghua University (DHU) (105-06-0019037), and the Research Foundation of the Key Laboratory of Textile Science & Technology (Ministry of Education, China).

Notes

^a The pH of all dispersions is 6–7.

^a At 517 nm.

^b At 314 nm.